May 2019 - Linux-kselftest-mirror

[PATCH v4 0/6] lib/string: Add strscpy_pad() function

by Tobin C. Harding

Hi Shua, Here is the set with cleanup as suggested by Kees on v3. Configured, built, and tested all modules loaded by tools/testing/selftests/lib/*.sh >From previous cover letters ... While doing the testing for strscpy_pad() it was noticed that there is duplication in how test modules are being fed to kselftest and also in the test modules themselves. This set makes an attempt at adding a framework to kselftest for writing kernel test modules. It also adds a script for use in creating script test runners for kselftest. My macro-foo is not great, all criticism and suggestions very much appreciated. The design is based on test modules lib/test_printf.c, lib/test_bitmap.c, lib/test_xarray.c. Changes since last version: - Remove dependency on Bash (thanks Kees) - Use oneliner to implement kselftest test runners (thanks Kees) - Squash patch that adds kselftest script creator script with patch that uses it. - Fix typos (thanks Randy) - Add Kees' Acked-by tags to all patches thanks, Tobin. Tobin C. Harding (6): lib/test_printf: Add empty module_exit function kselftest: Add test runner creation script kselftest: Add test module framework header lib: Use new kselftest header lib/string: Add strscpy_pad() function lib: Add test module for strscpy_pad Documentation/dev-tools/kselftest.rst | 94 +++++++++++- include/linux/string.h | 4 + lib/Kconfig.debug | 3 + lib/Makefile | 1 + lib/string.c | 47 +++++- lib/test_bitmap.c | 20 +-- lib/test_printf.c | 17 +-- lib/test_strscpy.c | 150 +++++++++++++++++++ tools/testing/selftests/kselftest_module.h | 48 ++++++ tools/testing/selftests/kselftest_module.sh | 84 +++++++++++ tools/testing/selftests/lib/Makefile | 2 +- tools/testing/selftests/lib/bitmap.sh | 18 +-- tools/testing/selftests/lib/config | 1 + tools/testing/selftests/lib/prime_numbers.sh | 17 +-- tools/testing/selftests/lib/printf.sh | 19 +-- tools/testing/selftests/lib/strscpy.sh | 3 + 16 files changed, 440 insertions(+), 88 deletions(-) create mode 100644 lib/test_strscpy.c create mode 100644 tools/testing/selftests/kselftest_module.h create mode 100755 tools/testing/selftests/kselftest_module.sh create mode 100755 tools/testing/selftests/lib/strscpy.sh -- 2.21.0

4 years, 8 months

5
11
0 0

[RFC v3 00/19] kunit: introduce KUnit, the Linux kernel unit testing framework

by Brendan Higgins

This patch set proposes KUnit, a lightweight unit testing and mocking framework for the Linux kernel. Unlike Autotest and kselftest, KUnit is a true unit testing framework; it does not require installing the kernel on a test machine or in a VM and does not require tests to be written in userspace running on a host kernel. Additionally, KUnit is fast: From invocation to completion KUnit can run several dozen tests in under a second. Currently, the entire KUnit test suite for KUnit runs in under a second from the initial invocation (build time excluded). KUnit is heavily inspired by JUnit, Python's unittest.mock, and Googletest/Googlemock for C++. KUnit provides facilities for defining unit test cases, grouping related test cases into test suites, providing common infrastructure for running tests, mocking, spying, and much more. ## What's so special about unit testing? A unit test is supposed to test a single unit of code in isolation, hence the name. There should be no dependencies outside the control of the test; this means no external dependencies, which makes tests orders of magnitudes faster. Likewise, since there are no external dependencies, there are no hoops to jump through to run the tests. Additionally, this makes unit tests deterministic: a failing unit test always indicates a problem. Finally, because unit tests necessarily have finer granularity, they are able to test all code paths easily solving the classic problem of difficulty in exercising error handling code. ## Is KUnit trying to replace other testing frameworks for the kernel? No. Most existing tests for the Linux kernel are end-to-end tests, which have their place. A well tested system has lots of unit tests, a reasonable number of integration tests, and some end-to-end tests. KUnit is just trying to address the unit test space which is currently not being addressed. ## More information on KUnit There is a bunch of documentation near the end of this patch set that describes how to use KUnit and best practices for writing unit tests. For convenience I am hosting the compiled docs here: https://google.github.io/kunit-docs/third_party/kernel/docs/ Additionally for convenience, I have applied these patches to a branch: https://kunit.googlesource.com/linux/+/kunit/rfc/4.19/v3 The repo may be cloned with: git clone https://kunit.googlesource.com/linux This patchset is on the kunit/rfc/4.19/v3 branch. ## Changes Since Last Version - Changed namespace prefix from `test_*` to `kunit_*` as requested by Shuah. - Started converting/cleaning up the device tree unittest to use KUnit. - Started adding KUnit expectations with custom messages. -- 2.20.0.rc0.387.gc7a69e6b6c-goog

4 years, 10 months

11
105
0 0

[PATCH v10 6/9] kselftests: cgroup: add freezer controller self-tests

by Roman Gushchin

This patch implements 9 tests for the freezer controller for cgroup v2: 1) a simple test, which aims to freeze and unfreeze a cgroup with 100 processes 2) a more complicated tree test, which creates a hierarchy of cgroups, puts some processes in some cgroups, and tries to freeze and unfreeze different parts of the subtree 3) a forkbomb test: the test aims to freeze a forkbomb running in a cgroup, kill all tasks in the cgroup and remove the cgroup without the unfreezing. 4) rmdir test: the test creates two nested cgroups, freezes the parent one, checks that the child can be successfully removed, and a new child can be created 5) migration tests: the test checks migration of a task between frozen cgroups: from a frozen to a running, from a running to a frozen, and from a frozen to a frozen. 6) ptrace test: the test checks that it's possible to attach to a process in a frozen cgroup, get some information and detach, and the cgroup will remain frozen. 7) stopped test: the test checks that it's possible to freeze a cgroup with a stopped task 8) ptraced test: the test checks that it's possible to freeze a cgroup with a ptraced task 9) vfork test: the test checks that it's possible to freeze a cgroup with a parent process waiting for the child process in vfork() Expected output: $ ./test_freezer ok 1 test_cgfreezer_simple ok 2 test_cgfreezer_tree ok 3 test_cgfreezer_forkbomb ok 4 test_cgrreezer_rmdir ok 5 test_cgfreezer_migrate ok 6 test_cgfreezer_ptrace ok 7 test_cgfreezer_stopped ok 8 test_cgfreezer_ptraced ok 9 test_cgfreezer_vfork Signed-off-by: Roman Gushchin <guro(a)fb.com> Cc: Shuah Khan <shuah(a)kernel.org> Cc: Tejun Heo <tj(a)kernel.org> Cc: kernel-team(a)fb.com Cc: linux-kselftest(a)vger.kernel.org --- tools/testing/selftests/cgroup/.gitignore | 1 + tools/testing/selftests/cgroup/Makefile | 2 + tools/testing/selftests/cgroup/cgroup_util.c | 54 +- tools/testing/selftests/cgroup/cgroup_util.h | 5 + tools/testing/selftests/cgroup/test_freezer.c | 851 ++++++++++++++++++ 5 files changed, 912 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/cgroup/test_freezer.c diff --git a/tools/testing/selftests/cgroup/.gitignore b/tools/testing/selftests/cgroup/.gitignore index adacda50a4b2..7f9835624793 100644 --- a/tools/testing/selftests/cgroup/.gitignore +++ b/tools/testing/selftests/cgroup/.gitignore @@ -1,2 +1,3 @@ test_memcontrol test_core +test_freezer diff --git a/tools/testing/selftests/cgroup/Makefile b/tools/testing/selftests/cgroup/Makefile index 23fbaa4a9630..8d369b6a2069 100644 --- a/tools/testing/selftests/cgroup/Makefile +++ b/tools/testing/selftests/cgroup/Makefile @@ -5,8 +5,10 @@ all: TEST_GEN_PROGS = test_memcontrol TEST_GEN_PROGS += test_core +TEST_GEN_PROGS += test_freezer include ../lib.mk $(OUTPUT)/test_memcontrol: cgroup_util.c $(OUTPUT)/test_core: cgroup_util.c +$(OUTPUT)/test_freezer: cgroup_util.c diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c index eba06f94433b..4c223266299a 100644 --- a/tools/testing/selftests/cgroup/cgroup_util.c +++ b/tools/testing/selftests/cgroup/cgroup_util.c @@ -74,6 +74,16 @@ char *cg_name_indexed(const char *root, const char *name, int index) return ret; } +char *cg_control(const char *cgroup, const char *control) +{ + size_t len = strlen(cgroup) + strlen(control) + 2; + char *ret = malloc(len); + + snprintf(ret, len, "%s/%s", cgroup, control); + + return ret; +} + int cg_read(const char *cgroup, const char *control, char *buf, size_t len) { char path[PATH_MAX]; @@ -196,7 +206,32 @@ int cg_create(const char *cgroup) return mkdir(cgroup, 0644); } -static int cg_killall(const char *cgroup) +int cg_wait_for_proc_count(const char *cgroup, int count) +{ + char buf[10 * PAGE_SIZE] = {0}; + int attempts; + char *ptr; + + for (attempts = 10; attempts >= 0; attempts--) { + int nr = 0; + + if (cg_read(cgroup, "cgroup.procs", buf, sizeof(buf))) + break; + + for (ptr = buf; *ptr; ptr++) + if (*ptr == '\n') + nr++; + + if (nr >= count) + return 0; + + usleep(100000); + } + + return -1; +} + +int cg_killall(const char *cgroup) { char buf[PAGE_SIZE]; char *ptr = buf; @@ -238,6 +273,14 @@ int cg_destroy(const char *cgroup) return ret; } +int cg_enter(const char *cgroup, int pid) +{ + char pidbuf[64]; + + snprintf(pidbuf, sizeof(pidbuf), "%d", pid); + return cg_write(cgroup, "cgroup.procs", pidbuf); +} + int cg_enter_current(const char *cgroup) { char pidbuf[64]; @@ -367,3 +410,12 @@ int set_oom_adj_score(int pid, int score) close(fd); return 0; } + +char proc_read_text(int pid, const char *item, char *buf, size_t size) +{ + char path[PATH_MAX]; + + snprintf(path, sizeof(path), "/proc/%d/%s", pid, item); + + return read_text(path, buf, size); +} diff --git a/tools/testing/selftests/cgroup/cgroup_util.h b/tools/testing/selftests/cgroup/cgroup_util.h index 9ac8b7958f83..c72f28046bfa 100644 --- a/tools/testing/selftests/cgroup/cgroup_util.h +++ b/tools/testing/selftests/cgroup/cgroup_util.h @@ -18,6 +18,7 @@ static inline int values_close(long a, long b, int err) extern int cg_find_unified_root(char *root, size_t len); extern char *cg_name(const char *root, const char *name); extern char *cg_name_indexed(const char *root, const char *name, int index); +extern char *cg_control(const char *cgroup, const char *control); extern int cg_create(const char *cgroup); extern int cg_destroy(const char *cgroup); extern int cg_read(const char *cgroup, const char *control, @@ -32,6 +33,7 @@ extern int cg_write(const char *cgroup, const char *control, char *buf); extern int cg_run(const char *cgroup, int (*fn)(const char *cgroup, void *arg), void *arg); +extern int cg_enter(const char *cgroup, int pid); extern int cg_enter_current(const char *cgroup); extern int cg_run_nowait(const char *cgroup, int (*fn)(const char *cgroup, void *arg), @@ -41,3 +43,6 @@ extern int alloc_pagecache(int fd, size_t size); extern int alloc_anon(const char *cgroup, void *arg); extern int is_swap_enabled(void); extern int set_oom_adj_score(int pid, int score); +extern int cg_wait_for_proc_count(const char *cgroup, int count); +extern int cg_killall(const char *cgroup); +extern char proc_read_text(int pid, const char *item, char *buf, size_t size); diff --git a/tools/testing/selftests/cgroup/test_freezer.c b/tools/testing/selftests/cgroup/test_freezer.c new file mode 100644 index 000000000000..2bfddb6d6d3b --- /dev/null +++ b/tools/testing/selftests/cgroup/test_freezer.c @@ -0,0 +1,851 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <stdbool.h> +#include <linux/limits.h> +#include <sys/ptrace.h> +#include <sys/types.h> +#include <sys/mman.h> +#include <unistd.h> +#include <stdio.h> +#include <errno.h> +#include <poll.h> +#include <stdlib.h> +#include <sys/inotify.h> +#include <string.h> +#include <sys/types.h> +#include <sys/wait.h> + +#include "../kselftest.h" +#include "cgroup_util.h" + +#define DEBUG +#ifdef DEBUG +#define debug(args...) fprintf(stderr, args) +#else +#define debug(args...) +#endif + +/* + * Check if the cgroup is frozen by looking at the cgroup.events::frozen value. + */ +static int cg_check_frozen(const char *cgroup, bool frozen) +{ + if (frozen) { + if (cg_read_strstr(cgroup, "cgroup.events", "frozen 1") != 0) { + debug("Cgroup %s isn't frozen\n", cgroup); + return -1; + } + } else { + /* + * Check the cgroup.events::frozen value. + */ + if (cg_read_strstr(cgroup, "cgroup.events", "frozen 0") != 0) { + debug("Cgroup %s is frozen\n", cgroup); + return -1; + } + } + + return 0; +} + +/* + * Freeze the given cgroup. + */ +static int cg_freeze_nowait(const char *cgroup, bool freeze) +{ + return cg_write(cgroup, "cgroup.freeze", freeze ? "1" : "0"); +} + +/* + * Prepare for waiting on cgroup.events file. + */ +static int cg_prepare_for_wait(const char *cgroup) +{ + int fd, ret = -1; + + fd = inotify_init1(0); + if (fd == -1) { + debug("Error: inotify_init1() failed\n"); + return fd; + } + + ret = inotify_add_watch(fd, cg_control(cgroup, "cgroup.events"), + IN_MODIFY); + if (ret == -1) { + debug("Error: inotify_add_watch() failed\n"); + close(fd); + } + + return fd; +} + +/* + * Wait for an event. If there are no events for 10 seconds, + * treat this an error. + */ +static int cg_wait_for(int fd) +{ + int ret = -1; + struct pollfd fds = { + .fd = fd, + .events = POLLIN, + }; + + while (true) { + ret = poll(&fds, 1, 10000); + + if (ret == -1) { + if (errno == EINTR) + continue; + debug("Error: poll() failed\n"); + break; + } + + if (ret > 0 && fds.revents & POLLIN) { + ret = 0; + break; + } + } + + return ret; +} + +/* + * Attach a task to the given cgroup and wait for a cgroup frozen event. + * All transient events (e.g. populated) are ignored. + */ +static int cg_enter_and_wait_for_frozen(const char *cgroup, int pid, + bool frozen) +{ + int fd, ret = -1; + int attempts; + + fd = cg_prepare_for_wait(cgroup); + if (fd < 0) + return fd; + + ret = cg_enter(cgroup, pid); + if (ret) + goto out; + + for (attempts = 0; attempts < 10; attempts++) { + ret = cg_wait_for(fd); + if (ret) + break; + + ret = cg_check_frozen(cgroup, frozen); + if (ret) + continue; + } + +out: + close(fd); + return ret; +} + +/* + * Freeze the given cgroup and wait for the inotify signal. + * If there are no events in 10 seconds, treat this as an error. + * Then check that the cgroup is in the desired state. + */ +static int cg_freeze_wait(const char *cgroup, bool freeze) +{ + int fd, ret = -1; + + fd = cg_prepare_for_wait(cgroup); + if (fd < 0) + return fd; + + ret = cg_freeze_nowait(cgroup, freeze); + if (ret) { + debug("Error: cg_freeze_nowait() failed\n"); + goto out; + } + + ret = cg_wait_for(fd); + if (ret) + goto out; + + ret = cg_check_frozen(cgroup, freeze); +out: + close(fd); + return ret; +} + +/* + * A simple process running in a sleep loop until being + * re-parented. + */ +static int child_fn(const char *cgroup, void *arg) +{ + int ppid = getppid(); + + while (getppid() == ppid) + usleep(1000); + + return getppid() == ppid; +} + +/* + * A simple test for the cgroup freezer: populated the cgroup with 100 + * running processes and freeze it. Then unfreeze it. Then it kills all + * processes and destroys the cgroup. + */ +static int test_cgfreezer_simple(const char *root) +{ + int ret = KSFT_FAIL; + char *cgroup = NULL; + int i; + + cgroup = cg_name(root, "cg_test_simple"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + for (i = 0; i < 100; i++) + cg_run_nowait(cgroup, child_fn, NULL); + + if (cg_wait_for_proc_count(cgroup, 100)) + goto cleanup; + + if (cg_check_frozen(cgroup, false)) + goto cleanup; + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + if (cg_freeze_wait(cgroup, false)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +/* + * The test creates the following hierarchy: + * A + * / / \ \ + * B E I K + * /\ | + * C D F + * | + * G + * | + * H + * + * with a process in C, H and 3 processes in K. + * Then it tries to freeze and unfreeze the whole tree. + */ +static int test_cgfreezer_tree(const char *root) +{ + char *cgroup[10] = {0}; + int ret = KSFT_FAIL; + int i; + + cgroup[0] = cg_name(root, "cg_test_tree_A"); + if (!cgroup[0]) + goto cleanup; + + cgroup[1] = cg_name(cgroup[0], "B"); + if (!cgroup[1]) + goto cleanup; + + cgroup[2] = cg_name(cgroup[1], "C"); + if (!cgroup[2]) + goto cleanup; + + cgroup[3] = cg_name(cgroup[1], "D"); + if (!cgroup[3]) + goto cleanup; + + cgroup[4] = cg_name(cgroup[0], "E"); + if (!cgroup[4]) + goto cleanup; + + cgroup[5] = cg_name(cgroup[4], "F"); + if (!cgroup[5]) + goto cleanup; + + cgroup[6] = cg_name(cgroup[5], "G"); + if (!cgroup[6]) + goto cleanup; + + cgroup[7] = cg_name(cgroup[6], "H"); + if (!cgroup[7]) + goto cleanup; + + cgroup[8] = cg_name(cgroup[0], "I"); + if (!cgroup[8]) + goto cleanup; + + cgroup[9] = cg_name(cgroup[0], "K"); + if (!cgroup[9]) + goto cleanup; + + for (i = 0; i < 10; i++) + if (cg_create(cgroup[i])) + goto cleanup; + + cg_run_nowait(cgroup[2], child_fn, NULL); + cg_run_nowait(cgroup[7], child_fn, NULL); + cg_run_nowait(cgroup[9], child_fn, NULL); + cg_run_nowait(cgroup[9], child_fn, NULL); + cg_run_nowait(cgroup[9], child_fn, NULL); + + /* + * Wait until all child processes will enter + * corresponding cgroups. + */ + + if (cg_wait_for_proc_count(cgroup[2], 1) || + cg_wait_for_proc_count(cgroup[7], 1) || + cg_wait_for_proc_count(cgroup[9], 3)) + goto cleanup; + + /* + * Freeze B. + */ + if (cg_freeze_wait(cgroup[1], true)) + goto cleanup; + + /* + * Freeze F. + */ + if (cg_freeze_wait(cgroup[5], true)) + goto cleanup; + + /* + * Freeze G. + */ + if (cg_freeze_wait(cgroup[6], true)) + goto cleanup; + + /* + * Check that A and E are not frozen. + */ + if (cg_check_frozen(cgroup[0], false)) + goto cleanup; + + if (cg_check_frozen(cgroup[4], false)) + goto cleanup; + + /* + * Freeze A. Check that A, B and E are frozen. + */ + if (cg_freeze_wait(cgroup[0], true)) + goto cleanup; + + if (cg_check_frozen(cgroup[1], true)) + goto cleanup; + + if (cg_check_frozen(cgroup[4], true)) + goto cleanup; + + /* + * Unfreeze B, F and G + */ + if (cg_freeze_nowait(cgroup[1], false)) + goto cleanup; + + if (cg_freeze_nowait(cgroup[5], false)) + goto cleanup; + + if (cg_freeze_nowait(cgroup[6], false)) + goto cleanup; + + /* + * Check that C and H are still frozen. + */ + if (cg_check_frozen(cgroup[2], true)) + goto cleanup; + + if (cg_check_frozen(cgroup[7], true)) + goto cleanup; + + /* + * Unfreeze A. Check that A, C and K are not frozen. + */ + if (cg_freeze_wait(cgroup[0], false)) + goto cleanup; + + if (cg_check_frozen(cgroup[2], false)) + goto cleanup; + + if (cg_check_frozen(cgroup[9], false)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + for (i = 9; i >= 0 && cgroup[i]; i--) { + cg_destroy(cgroup[i]); + free(cgroup[i]); + } + + return ret; +} + +/* + * A fork bomb emulator. + */ +static int forkbomb_fn(const char *cgroup, void *arg) +{ + int ppid; + + fork(); + fork(); + + ppid = getppid(); + + while (getppid() == ppid) + usleep(1000); + + return getppid() == ppid; +} + +/* + * The test runs a fork bomb in a cgroup and tries to freeze it. + * Then it kills all processes and checks that cgroup isn't populated + * anymore. + */ +static int test_cgfreezer_forkbomb(const char *root) +{ + int ret = KSFT_FAIL; + char *cgroup = NULL; + + cgroup = cg_name(root, "cg_forkbomb_test"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + cg_run_nowait(cgroup, forkbomb_fn, NULL); + + usleep(100000); + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + if (cg_killall(cgroup)) + goto cleanup; + + if (cg_wait_for_proc_count(cgroup, 0)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +/* + * The test creates two nested cgroups, freezes the parent + * and removes the child. Then it checks that the parent cgroup + * remains frozen and it's possible to create a new child + * without unfreezing. The new child is frozen too. + */ +static int test_cgfreezer_rmdir(const char *root) +{ + int ret = KSFT_FAIL; + char *parent, *child = NULL; + + parent = cg_name(root, "cg_test_rmdir_A"); + if (!parent) + goto cleanup; + + child = cg_name(parent, "cg_test_rmdir_B"); + if (!child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_freeze_wait(parent, true)) + goto cleanup; + + if (cg_destroy(child)) + goto cleanup; + + if (cg_check_frozen(parent, true)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_check_frozen(child, true)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (child) + cg_destroy(child); + free(child); + if (parent) + cg_destroy(parent); + free(parent); + return ret; +} + +/* + * The test creates two cgroups: A and B, runs a process in A + * and performs several migrations: + * 1) A (running) -> B (frozen) + * 2) B (frozen) -> A (running) + * 3) A (frozen) -> B (frozen) + * + * On each step it checks the actual state of both cgroups. + */ +static int test_cgfreezer_migrate(const char *root) +{ + int ret = KSFT_FAIL; + char *cgroup[2] = {0}; + int pid; + + cgroup[0] = cg_name(root, "cg_test_migrate_A"); + if (!cgroup[0]) + goto cleanup; + + cgroup[1] = cg_name(root, "cg_test_migrate_B"); + if (!cgroup[1]) + goto cleanup; + + if (cg_create(cgroup[0])) + goto cleanup; + + if (cg_create(cgroup[1])) + goto cleanup; + + pid = cg_run_nowait(cgroup[0], child_fn, NULL); + if (pid < 0) + goto cleanup; + + if (cg_wait_for_proc_count(cgroup[0], 1)) + goto cleanup; + + /* + * Migrate from A (running) to B (frozen) + */ + if (cg_freeze_wait(cgroup[1], true)) + goto cleanup; + + if (cg_enter_and_wait_for_frozen(cgroup[1], pid, true)) + goto cleanup; + + if (cg_check_frozen(cgroup[0], false)) + goto cleanup; + + /* + * Migrate from B (frozen) to A (running) + */ + if (cg_enter_and_wait_for_frozen(cgroup[0], pid, false)) + goto cleanup; + + if (cg_check_frozen(cgroup[1], true)) + goto cleanup; + + /* + * Migrate from A (frozen) to B (frozen) + */ + if (cg_freeze_wait(cgroup[0], true)) + goto cleanup; + + if (cg_enter_and_wait_for_frozen(cgroup[1], pid, true)) + goto cleanup; + + if (cg_check_frozen(cgroup[0], true)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup[0]) + cg_destroy(cgroup[0]); + free(cgroup[0]); + if (cgroup[1]) + cg_destroy(cgroup[1]); + free(cgroup[1]); + return ret; +} + +/* + * The test checks that ptrace works with a tracing process in a frozen cgroup. + */ +static int test_cgfreezer_ptrace(const char *root) +{ + int ret = KSFT_FAIL; + char *cgroup = NULL; + siginfo_t siginfo; + int pid; + + cgroup = cg_name(root, "cg_test_ptrace"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + pid = cg_run_nowait(cgroup, child_fn, NULL); + if (pid < 0) + goto cleanup; + + if (cg_wait_for_proc_count(cgroup, 1)) + goto cleanup; + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + if (ptrace(PTRACE_SEIZE, pid, NULL, NULL)) + goto cleanup; + + if (ptrace(PTRACE_INTERRUPT, pid, NULL, NULL)) + goto cleanup; + + waitpid(pid, NULL, 0); + + /* + * Cgroup has to remain frozen, however the test task + * is in traced state. + */ + if (cg_check_frozen(cgroup, true)) + goto cleanup; + + if (ptrace(PTRACE_GETSIGINFO, pid, NULL, &siginfo)) + goto cleanup; + + if (ptrace(PTRACE_DETACH, pid, NULL, NULL)) + goto cleanup; + + if (cg_check_frozen(cgroup, true)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +/* + * Check if the process is stopped. + */ +static int proc_check_stopped(int pid) +{ + char buf[PAGE_SIZE]; + int len; + + len = proc_read_text(pid, "stat", buf, sizeof(buf)); + if (len == -1) { + debug("Can't get %d stat\n", pid); + return -1; + } + + if (strstr(buf, "(test_freezer) T ") == NULL) { + debug("Process %d in the unexpected state: %s\n", pid, buf); + return -1; + } + + return 0; +} + +/* + * Test that it's possible to freeze a cgroup with a stopped process. + */ +static int test_cgfreezer_stopped(const char *root) +{ + int pid, ret = KSFT_FAIL; + char *cgroup = NULL; + + cgroup = cg_name(root, "cg_test_stopped"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + pid = cg_run_nowait(cgroup, child_fn, NULL); + + if (cg_wait_for_proc_count(cgroup, 1)) + goto cleanup; + + if (kill(pid, SIGSTOP)) + goto cleanup; + + if (cg_check_frozen(cgroup, false)) + goto cleanup; + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + if (cg_freeze_wait(cgroup, false)) + goto cleanup; + + if (proc_check_stopped(pid)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +/* + * Test that it's possible to freeze a cgroup with a ptraced process. + */ +static int test_cgfreezer_ptraced(const char *root) +{ + int pid, ret = KSFT_FAIL; + char *cgroup = NULL; + siginfo_t siginfo; + + cgroup = cg_name(root, "cg_test_ptraced"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + pid = cg_run_nowait(cgroup, child_fn, NULL); + + if (cg_wait_for_proc_count(cgroup, 1)) + goto cleanup; + + if (ptrace(PTRACE_SEIZE, pid, NULL, NULL)) + goto cleanup; + + if (ptrace(PTRACE_INTERRUPT, pid, NULL, NULL)) + goto cleanup; + + waitpid(pid, NULL, 0); + + if (cg_check_frozen(cgroup, false)) + goto cleanup; + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + /* + * cg_check_frozen(cgroup, true) will fail here, + * because the task in in the TRACEd state. + */ + if (cg_freeze_wait(cgroup, false)) + goto cleanup; + + if (ptrace(PTRACE_GETSIGINFO, pid, NULL, &siginfo)) + goto cleanup; + + if (ptrace(PTRACE_DETACH, pid, NULL, NULL)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +static int vfork_fn(const char *cgroup, void *arg) +{ + int pid = vfork(); + + if (pid == 0) + while (true) + sleep(1); + + return pid; +} + +/* + * Test that it's possible to freeze a cgroup with a process, + * which called vfork() and is waiting for a child. + */ +static int test_cgfreezer_vfork(const char *root) +{ + int ret = KSFT_FAIL; + char *cgroup = NULL; + + cgroup = cg_name(root, "cg_test_vfork"); + if (!cgroup) + goto cleanup; + + if (cg_create(cgroup)) + goto cleanup; + + cg_run_nowait(cgroup, vfork_fn, NULL); + + if (cg_wait_for_proc_count(cgroup, 2)) + goto cleanup; + + if (cg_freeze_wait(cgroup, true)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (cgroup) + cg_destroy(cgroup); + free(cgroup); + return ret; +} + +#define T(x) { x, #x } +struct cgfreezer_test { + int (*fn)(const char *root); + const char *name; +} tests[] = { + T(test_cgfreezer_simple), + T(test_cgfreezer_tree), + T(test_cgfreezer_forkbomb), + T(test_cgfreezer_rmdir), + T(test_cgfreezer_migrate), + T(test_cgfreezer_ptrace), + T(test_cgfreezer_stopped), + T(test_cgfreezer_ptraced), + T(test_cgfreezer_vfork), +}; +#undef T + +int main(int argc, char *argv[]) +{ + char root[PATH_MAX]; + int i, ret = EXIT_SUCCESS; + + if (cg_find_unified_root(root, sizeof(root))) + ksft_exit_skip("cgroup v2 isn't mounted\n"); + for (i = 0; i < ARRAY_SIZE(tests); i++) { + switch (tests[i].fn(root)) { + case KSFT_PASS: + ksft_test_result_pass("%s\n", tests[i].name); + break; + case KSFT_SKIP: + ksft_test_result_skip("%s\n", tests[i].name); + break; + default: + ret = EXIT_FAILURE; + ksft_test_result_fail("%s\n", tests[i].name); + break; + } + } + + return ret; +} -- 2.20.1

5 years

3
4
0 0

[PATCH v6 00/19] Unify vDSOs across more architectures

by Vincenzo Frascino

vDSO (virtual dynamic shared object) is a mechanism that the Linux kernel provides as an alternative to system calls to reduce where possible the costs in terms of cycles. This is possible because certain syscalls like gettimeofday() do not write any data and return one or more values that are stored in the kernel, which makes relatively safe calling them directly as a library function. Even if the mechanism is pretty much standard, every architecture in the last few years ended up implementing their own vDSO library in the architectural code. The purpose of this patch-set is to identify the commonalities in between the architectures and try to consolidate the common code paths, starting with gettimeofday(). This implementation contains the following design choices: * Every architecture defines the arch specific code in an header in "asm/vdso/". * The generic implementation includes the arch specific one and lives in "lib/vdso". * The arch specific code for gettimeofday lives in "<arch path>/vdso/gettimeofday.c" and includes the generic code only. * The generic implementation of update_vsyscall and update_vsyscall_tz lives in kernel/vdso and provide the bindings that can be implemented by each architecture. * Each architecture provides its implementation of the bindings in "asm/vdso/vsyscall.h". * This approach allows to consolidate the common code in a single place with the benefit of avoiding code duplication. This implementation contains the portings to the common library for: arm64, compat mode for arm64, arm, mips, x86_64, x32, compat mode for x86_64 and i386. The mips porting has been tested on qemu for mips32el. A configuration to repeat the tests can be found at [4]. The x86_64 porting has been tested on an Intel Xeon 5120T based machine running Ubuntu 18.04 and using the Ubuntu provided defconfig. The i386 porting has been tested on qemu using the i386_defconfig configuration. Last but not least from this porting arm64, compat arm64, arm and mips gain the support for: * CLOCK_BOOTTIME that can be useful in certain scenarios since it keeps track of the time during sleep as well. * CLOCK_TAI that is like CLOCK_REALTIME, but uses the International Atomic Time (TAI) reference instead of UTC to avoid jumping on leap second updates. for both clock_gettime and clock_getres. The porting has been validated using the vdsotest test-suite [1] extended to cover all the clock ids [2]. A new test has been added to the linux kselftest in order to validate the newly added library. The porting has been benchmarked and the performance results are provided as part of this cover letter. To simplify the testing, a copy of the patchset on top of a recent linux tree can be found at [3] and [4]. [1] https://github.com/nathanlynch/vdsotest [2] https://github.com/fvincenzo/vdsotest [3] git://linux-arm.org/linux-vf.git vdso/v6 [4] git://linux-arm.org/linux-vf.git vdso-mips/v6 Changes: -------- v6: - Rebased on 5.2-rc2. - Added performance numbers. - Removed vdso_types.h. - Unified update_vsyscall and update_vsyscall_tz. - Reworked the kselftest included in this patchset. - Addressed review comments. v5: - Rebased on 5.0-rc7. - Added x86_64, compat mode for x86_64 and i386 portings. - Extended vDSO kselftest. - Addressed review comments. v4: - Rebased on 5.0-rc2. - Addressed review comments. - Disabled compat vdso on arm64 when the kernel is compiled with clang. v3: - Ported the latest fixes and optimizations done on the x86 architecture to the generic library. - Addressed review comments. - Improved the documentation of the interfaces. - Changed the HAVE_ARCH_TIMER config option to a more generic HAVE_HW_COUNTER. v2: - Added -ffixed-x18 to arm64 - Repleced occurrences of timeval and timespec - Modified datapage.h to be compliant with y2038 on all the architectures - Removed __u_vdso type Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: Will Deacon <will.deacon(a)arm.com> Cc: Arnd Bergmann <arnd(a)arndb.de> Cc: Russell King <linux(a)armlinux.org.uk> Cc: Ralf Baechle <ralf(a)linux-mips.org> Cc: Paul Burton <paul.burton(a)mips.com> Cc: Daniel Lezcano <daniel.lezcano(a)linaro.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: Mark Salyzyn <salyzyn(a)android.com> Cc: Peter Collingbourne <pcc(a)google.com> Cc: Shuah Khan <shuah(a)kernel.org> Cc: Dmitry Safonov <0x7f454c46(a)gmail.com> Cc: Rasmus Villemoes <linux(a)rasmusvillemoes.dk> Cc: Huw Davies <huw(a)codeweavers.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino(a)arm.com> Performance Numbers: Linux 5.2.0-rc2 - Xeon Gold 5120T ====================================================== Unified vDSO: ------------- clock-gettime-monotonic: syscall: 342 nsec/call clock-gettime-monotonic: libc: 25 nsec/call clock-gettime-monotonic: vdso: 24 nsec/call clock-getres-monotonic: syscall: 296 nsec/call clock-getres-monotonic: libc: 296 nsec/call clock-getres-monotonic: vdso: 3 nsec/call clock-gettime-monotonic-coarse: syscall: 294 nsec/call clock-gettime-monotonic-coarse: libc: 5 nsec/call clock-gettime-monotonic-coarse: vdso: 5 nsec/call clock-getres-monotonic-coarse: syscall: 295 nsec/call clock-getres-monotonic-coarse: libc: 292 nsec/call clock-getres-monotonic-coarse: vdso: 5 nsec/call clock-gettime-monotonic-raw: syscall: 343 nsec/call clock-gettime-monotonic-raw: libc: 25 nsec/call clock-gettime-monotonic-raw: vdso: 23 nsec/call clock-getres-monotonic-raw: syscall: 290 nsec/call clock-getres-monotonic-raw: libc: 290 nsec/call clock-getres-monotonic-raw: vdso: 4 nsec/call clock-gettime-tai: syscall: 332 nsec/call clock-gettime-tai: libc: 24 nsec/call clock-gettime-tai: vdso: 23 nsec/call clock-getres-tai: syscall: 288 nsec/call clock-getres-tai: libc: 288 nsec/call clock-getres-tai: vdso: 3 nsec/call clock-gettime-boottime: syscall: 342 nsec/call clock-gettime-boottime: libc: 24 nsec/call clock-gettime-boottime: vdso: 23 nsec/call clock-getres-boottime: syscall: 284 nsec/call clock-getres-boottime: libc: 291 nsec/call clock-getres-boottime: vdso: 3 nsec/call clock-gettime-realtime: syscall: 337 nsec/call clock-gettime-realtime: libc: 24 nsec/call clock-gettime-realtime: vdso: 23 nsec/call clock-getres-realtime: syscall: 287 nsec/call clock-getres-realtime: libc: 284 nsec/call clock-getres-realtime: vdso: 3 nsec/call clock-gettime-realtime-coarse: syscall: 307 nsec/call clock-gettime-realtime-coarse: libc: 4 nsec/call clock-gettime-realtime-coarse: vdso: 4 nsec/call clock-getres-realtime-coarse: syscall: 294 nsec/call clock-getres-realtime-coarse: libc: 291 nsec/call clock-getres-realtime-coarse: vdso: 4 nsec/call getcpu: syscall: 246 nsec/call getcpu: libc: 14 nsec/call getcpu: vdso: 11 nsec/call gettimeofday: syscall: 293 nsec/call gettimeofday: libc: 26 nsec/call gettimeofday: vdso: 25 nsec/call Stock Kernel: ------------- clock-gettime-monotonic: syscall: 338 nsec/call clock-gettime-monotonic: libc: 24 nsec/call clock-gettime-monotonic: vdso: 23 nsec/call clock-getres-monotonic: syscall: 291 nsec/call clock-getres-monotonic: libc: 304 nsec/call clock-getres-monotonic: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-monotonic-coarse: syscall: 297 nsec/call clock-gettime-monotonic-coarse: libc: 5 nsec/call clock-gettime-monotonic-coarse: vdso: 4 nsec/call clock-getres-monotonic-coarse: syscall: 281 nsec/call clock-getres-monotonic-coarse: libc: 286 nsec/call clock-getres-monotonic-coarse: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-monotonic-raw: syscall: 336 nsec/call clock-gettime-monotonic-raw: libc: 340 nsec/call clock-gettime-monotonic-raw: vdso: 346 nsec/call clock-getres-monotonic-raw: syscall: 297 nsec/call clock-getres-monotonic-raw: libc: 301 nsec/call clock-getres-monotonic-raw: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-tai: syscall: 351 nsec/call clock-gettime-tai: libc: 24 nsec/call clock-gettime-tai: vdso: 23 nsec/call clock-getres-tai: syscall: 298 nsec/call clock-getres-tai: libc: 290 nsec/call clock-getres-tai: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-boottime: syscall: 342 nsec/call clock-gettime-boottime: libc: 347 nsec/call clock-gettime-boottime: vdso: 355 nsec/call clock-getres-boottime: syscall: 296 nsec/call clock-getres-boottime: libc: 295 nsec/call clock-getres-boottime: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-realtime: syscall: 346 nsec/call clock-gettime-realtime: libc: 24 nsec/call clock-gettime-realtime: vdso: 22 nsec/call clock-getres-realtime: syscall: 295 nsec/call clock-getres-realtime: libc: 291 nsec/call clock-getres-realtime: vdso: not tested Note: vDSO version of clock_getres not found clock-gettime-realtime-coarse: syscall: 292 nsec/call clock-gettime-realtime-coarse: libc: 5 nsec/call clock-gettime-realtime-coarse: vdso: 4 nsec/call clock-getres-realtime-coarse: syscall: 300 nsec/call clock-getres-realtime-coarse: libc: 301 nsec/call clock-getres-realtime-coarse: vdso: not tested Note: vDSO version of clock_getres not found getcpu: syscall: 252 nsec/call getcpu: libc: 14 nsec/call getcpu: vdso: 11 nsec/call gettimeofday: syscall: 293 nsec/call gettimeofday: libc: 24 nsec/call gettimeofday: vdso: 25 nsec/call Peter Collingbourne (1): arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino (18): kernel: Standardize vdso_datapage kernel: Define gettimeofday vdso common code kernel: Unify update_vsyscall implementation arm64: Substitute gettimeofday with C implementation arm64: compat: Add missing syscall numbers arm64: compat: Expose signal related structures arm64: compat: Generate asm offsets for signals lib: vdso: Add compat support arm64: compat: Add vDSO arm64: Refactor vDSO code arm64: compat: vDSO setup for compat layer arm64: elf: vDSO code page discovery arm64: compat: Get sigreturn trampolines from vDSO arm64: Add vDSO compat support arm: Add support for generic vDSO mips: Add support for generic vDSO x86: Add support for generic vDSO kselftest: Extend vDSO selftest arch/arm/Kconfig | 3 + arch/arm/include/asm/vdso/gettimeofday.h | 96 +++++ arch/arm/include/asm/vdso/vsyscall.h | 71 ++++ arch/arm/include/asm/vdso_datapage.h | 29 +- arch/arm/kernel/vdso.c | 87 +---- arch/arm/vdso/Makefile | 13 +- arch/arm/vdso/note.c | 15 + arch/arm/vdso/vdso.lds.S | 2 + arch/arm/vdso/vgettimeofday.c | 268 +------------ arch/arm64/Kconfig | 3 + arch/arm64/Makefile | 23 +- arch/arm64/include/asm/elf.h | 14 + arch/arm64/include/asm/signal32.h | 46 +++ arch/arm64/include/asm/unistd.h | 5 + arch/arm64/include/asm/vdso.h | 3 + arch/arm64/include/asm/vdso/compat_barrier.h | 51 +++ .../include/asm/vdso/compat_gettimeofday.h | 108 ++++++ arch/arm64/include/asm/vdso/gettimeofday.h | 84 +++++ arch/arm64/include/asm/vdso/vsyscall.h | 53 +++ arch/arm64/include/asm/vdso_datapage.h | 48 --- arch/arm64/kernel/Makefile | 6 +- arch/arm64/kernel/asm-offsets.c | 39 +- arch/arm64/kernel/signal32.c | 72 ++-- arch/arm64/kernel/vdso.c | 356 ++++++++++++------ arch/arm64/kernel/vdso/Makefile | 34 +- arch/arm64/kernel/vdso/gettimeofday.S | 334 ---------------- arch/arm64/kernel/vdso/vgettimeofday.c | 28 ++ arch/arm64/kernel/vdso32/.gitignore | 2 + arch/arm64/kernel/vdso32/Makefile | 184 +++++++++ arch/arm64/kernel/vdso32/note.c | 15 + arch/arm64/kernel/vdso32/sigreturn.S | 62 +++ arch/arm64/kernel/vdso32/vdso.S | 19 + arch/arm64/kernel/vdso32/vdso.lds.S | 82 ++++ arch/arm64/kernel/vdso32/vgettimeofday.c | 59 +++ arch/mips/Kconfig | 2 + arch/mips/include/asm/vdso.h | 78 +--- arch/mips/include/asm/vdso/gettimeofday.h | 175 +++++++++ arch/mips/{ => include/asm}/vdso/vdso.h | 6 +- arch/mips/include/asm/vdso/vsyscall.h | 43 +++ arch/mips/kernel/vdso.c | 37 +- arch/mips/vdso/Makefile | 25 +- arch/mips/vdso/elf.S | 2 +- arch/mips/vdso/gettimeofday.c | 273 -------------- arch/mips/vdso/sigreturn.S | 2 +- arch/mips/vdso/vdso.lds.S | 4 + arch/mips/vdso/vgettimeofday.c | 57 +++ arch/x86/Kconfig | 3 + arch/x86/entry/vdso/Makefile | 9 + arch/x86/entry/vdso/vclock_gettime.c | 251 +++--------- arch/x86/entry/vdso/vdso.lds.S | 2 + arch/x86/entry/vdso/vdso32/vdso32.lds.S | 2 + arch/x86/entry/vdso/vdsox32.lds.S | 1 + arch/x86/entry/vsyscall/Makefile | 2 - arch/x86/entry/vsyscall/vsyscall_gtod.c | 83 ---- arch/x86/include/asm/mshyperv-tsc.h | 76 ++++ arch/x86/include/asm/mshyperv.h | 70 +--- arch/x86/include/asm/pvclock.h | 2 +- arch/x86/include/asm/vdso/gettimeofday.h | 203 ++++++++++ arch/x86/include/asm/vdso/vsyscall.h | 44 +++ arch/x86/include/asm/vgtod.h | 75 +--- arch/x86/include/asm/vvar.h | 7 +- arch/x86/kernel/pvclock.c | 1 + include/asm-generic/vdso/vsyscall.h | 56 +++ include/linux/hrtimer.h | 15 +- include/linux/hrtimer_defs.h | 25 ++ include/linux/timekeeper_internal.h | 9 + include/vdso/datapage.h | 91 +++++ include/vdso/helpers.h | 56 +++ include/vdso/vsyscall.h | 11 + kernel/Makefile | 1 + kernel/vdso/Makefile | 2 + kernel/vdso/vsyscall.c | 139 +++++++ lib/Kconfig | 5 + lib/vdso/Kconfig | 36 ++ lib/vdso/Makefile | 22 ++ lib/vdso/gettimeofday.c | 229 +++++++++++ tools/testing/selftests/vDSO/Makefile | 2 + tools/testing/selftests/vDSO/vdso_full_test.c | 261 +++++++++++++ 78 files changed, 3042 insertions(+), 1767 deletions(-) create mode 100644 arch/arm/include/asm/vdso/gettimeofday.h create mode 100644 arch/arm/include/asm/vdso/vsyscall.h create mode 100644 arch/arm/vdso/note.c create mode 100644 arch/arm64/include/asm/vdso/compat_barrier.h create mode 100644 arch/arm64/include/asm/vdso/compat_gettimeofday.h create mode 100644 arch/arm64/include/asm/vdso/gettimeofday.h create mode 100644 arch/arm64/include/asm/vdso/vsyscall.h delete mode 100644 arch/arm64/include/asm/vdso_datapage.h delete mode 100644 arch/arm64/kernel/vdso/gettimeofday.S create mode 100644 arch/arm64/kernel/vdso/vgettimeofday.c create mode 100644 arch/arm64/kernel/vdso32/.gitignore create mode 100644 arch/arm64/kernel/vdso32/Makefile create mode 100644 arch/arm64/kernel/vdso32/note.c create mode 100644 arch/arm64/kernel/vdso32/sigreturn.S create mode 100644 arch/arm64/kernel/vdso32/vdso.S create mode 100644 arch/arm64/kernel/vdso32/vdso.lds.S create mode 100644 arch/arm64/kernel/vdso32/vgettimeofday.c create mode 100644 arch/mips/include/asm/vdso/gettimeofday.h rename arch/mips/{ => include/asm}/vdso/vdso.h (90%) create mode 100644 arch/mips/include/asm/vdso/vsyscall.h delete mode 100644 arch/mips/vdso/gettimeofday.c create mode 100644 arch/mips/vdso/vgettimeofday.c delete mode 100644 arch/x86/entry/vsyscall/vsyscall_gtod.c create mode 100644 arch/x86/include/asm/mshyperv-tsc.h create mode 100644 arch/x86/include/asm/vdso/gettimeofday.h create mode 100644 arch/x86/include/asm/vdso/vsyscall.h create mode 100644 include/asm-generic/vdso/vsyscall.h create mode 100644 include/linux/hrtimer_defs.h create mode 100644 include/vdso/datapage.h create mode 100644 include/vdso/helpers.h create mode 100644 include/vdso/vsyscall.h create mode 100644 kernel/vdso/Makefile create mode 100644 kernel/vdso/vsyscall.c create mode 100644 lib/vdso/Kconfig create mode 100644 lib/vdso/Makefile create mode 100644 lib/vdso/gettimeofday.c create mode 100644 tools/testing/selftests/vDSO/vdso_full_test.c -- 2.21.0

5 years

11
68
0 0

[PATCH v3 1/2] pid: add pidfd_open()

by Christian Brauner

This adds the pidfd_open() syscall. It allows a caller to retrieve pollable pidfds for a process which did not get created via CLONE_PIDFD, i.e. for a process that is created via traditional fork()/clone() calls that is only referenced by a PID: int pidfd = pidfd_open(1234, 0); ret = pidfd_send_signal(pidfd, SIGSTOP, NULL, 0); With the introduction of pidfds through CLONE_PIDFD it is possible to created pidfds at process creation time. However, a lot of processes get created with traditional PID-based calls such as fork() or clone() (without CLONE_PIDFD). For these processes a caller can currently not create a pollable pidfd. This is a problem for Android's low memory killer (LMK) and service managers such as systemd. Both are examples of tools that want to make use of pidfds to get reliable notification of process exit for non-parents (pidfd polling) and race-free signal sending (pidfd_send_signal()). They intend to switch to this API for process supervision/management as soon as possible. Having no way to get pollable pidfds from PID-only processes is one of the biggest blockers for them in adopting this api. With pidfd_open() making it possible to retrieve pidfds for PID-based processes we enable them to adopt this api. In line with Arnd's recent changes to consolidate syscall numbers across architectures, I have added the pidfd_open() syscall to all architectures at the same time. Signed-off-by: Christian Brauner <christian(a)brauner.io> Reviewed-by: Oleg Nesterov <oleg(a)redhat.com> Acked-by: Arnd Bergmann <arnd(a)arndb.de> Cc: "Eric W. Biederman" <ebiederm(a)xmission.com> Cc: Kees Cook <keescook(a)chromium.org> Cc: Joel Fernandes (Google) <joel(a)joelfernandes.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: Jann Horn <jannh(a)google.com> Cc: David Howells <dhowells(a)redhat.com> Cc: Andy Lutomirsky <luto(a)kernel.org> Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: Aleksa Sarai <cyphar(a)cyphar.com> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Al Viro <viro(a)zeniv.linux.org.uk> Cc: linux-api(a)vger.kernel.org --- v1: - kbuild test robot <lkp(a)intel.com>: - add missing entry for pidfd_open to arch/arm/tools/syscall.tbl - Oleg Nesterov <oleg(a)redhat.com>: - use simpler thread-group leader check v2: - Oleg Nesterov <oleg(a)redhat.com>: - avoid using additional variable - remove unneeded comment - Arnd Bergmann <arnd(a)arndb.de>: - switch from 428 to 434 since the new mount api has taken it - bump syscall numbers in arch/arm64/include/asm/unistd.h - Joel Fernandes (Google) <joel(a)joelfernandes.org>: - switch from ESRCH to EINVAL when the passed-in pid does not refer to a thread-group leader - Christian Brauner <christian(a)brauner.io>: - rebase on v5.2-rc1 - adapt syscall number to account for new mount api syscalls v3: - Arnd Bergmann <arnd(a)arndb.de>: - add missing syscall entries for mips-o32 and mips-n64 --- arch/alpha/kernel/syscalls/syscall.tbl | 1 + arch/arm/tools/syscall.tbl | 1 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 2 + arch/ia64/kernel/syscalls/syscall.tbl | 1 + arch/m68k/kernel/syscalls/syscall.tbl | 1 + arch/microblaze/kernel/syscalls/syscall.tbl | 1 + arch/mips/kernel/syscalls/syscall_n32.tbl | 1 + arch/mips/kernel/syscalls/syscall_n64.tbl | 1 + arch/mips/kernel/syscalls/syscall_o32.tbl | 1 + arch/parisc/kernel/syscalls/syscall.tbl | 1 + arch/powerpc/kernel/syscalls/syscall.tbl | 1 + arch/s390/kernel/syscalls/syscall.tbl | 1 + arch/sh/kernel/syscalls/syscall.tbl | 1 + arch/sparc/kernel/syscalls/syscall.tbl | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/xtensa/kernel/syscalls/syscall.tbl | 1 + include/linux/pid.h | 1 + include/linux/syscalls.h | 1 + include/uapi/asm-generic/unistd.h | 4 +- kernel/fork.c | 2 +- kernel/pid.c | 43 +++++++++++++++++++++ 23 files changed, 68 insertions(+), 3 deletions(-) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 9e7704e44f6d..1db9bbcfb84e 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -473,3 +473,4 @@ 541 common fsconfig sys_fsconfig 542 common fsmount sys_fsmount 543 common fspick sys_fspick +544 common pidfd_open sys_pidfd_open diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index aaf479a9e92d..81e6e1817c45 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -447,3 +447,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 70e6882853c0..e8f7d95a1481 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -44,7 +44,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 434 +#define __NR_compat_syscalls 435 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index c39e90600bb3..7a3158ccd68e 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -886,6 +886,8 @@ __SYSCALL(__NR_fsconfig, sys_fsconfig) __SYSCALL(__NR_fsmount, sys_fsmount) #define __NR_fspick 433 __SYSCALL(__NR_fspick, sys_fspick) +#define __NR_pidfd_open 434 +__SYSCALL(__NR_pidfd_open, sys_pidfd_open) /* * Please add new compat syscalls above this comment and update diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl index e01df3f2f80d..ecc44926737b 100644 --- a/arch/ia64/kernel/syscalls/syscall.tbl +++ b/arch/ia64/kernel/syscalls/syscall.tbl @@ -354,3 +354,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index 7e3d0734b2f3..9a3eb2558568 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -433,3 +433,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index 26339e417695..ad706f83c755 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -439,3 +439,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 0e2dd68ade57..97035e19ad03 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -372,3 +372,4 @@ 431 n32 fsconfig sys_fsconfig 432 n32 fsmount sys_fsmount 433 n32 fspick sys_fspick +434 n32 pidfd_open sys_pidfd_open diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index 5eebfa0d155c..d7292722d3b0 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -348,3 +348,4 @@ 431 n64 fsconfig sys_fsconfig 432 n64 fsmount sys_fsmount 433 n64 fspick sys_fspick +434 n64 pidfd_open sys_pidfd_open diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 3cc1374e02d0..dba084c92f14 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -421,3 +421,4 @@ 431 o32 fsconfig sys_fsconfig 432 o32 fsmount sys_fsmount 433 o32 fspick sys_fspick +434 o32 pidfd_open sys_pidfd_open diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index c9e377d59232..5022b9e179c2 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -430,3 +430,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index 103655d84b4b..f2c3bda2d39f 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -515,3 +515,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index e822b2964a83..6ebacfeaf853 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -436,3 +436,4 @@ 431 common fsconfig sys_fsconfig sys_fsconfig 432 common fsmount sys_fsmount sys_fsmount 433 common fspick sys_fspick sys_fspick +434 common pidfd_open sys_pidfd_open sys_pidfd_open diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index 016a727d4357..834c9c7d79fa 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -436,3 +436,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index e047480b1605..c58e71f21129 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -479,3 +479,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index ad968b7bac72..43e4429a5272 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -438,3 +438,4 @@ 431 i386 fsconfig sys_fsconfig __ia32_sys_fsconfig 432 i386 fsmount sys_fsmount __ia32_sys_fsmount 433 i386 fspick sys_fspick __ia32_sys_fspick +434 i386 pidfd_open sys_pidfd_open __ia32_sys_pidfd_open diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index b4e6f9e6204a..1bee0a77fdd3 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -355,6 +355,7 @@ 431 common fsconfig __x64_sys_fsconfig 432 common fsmount __x64_sys_fsmount 433 common fspick __x64_sys_fspick +434 common pidfd_open __x64_sys_pidfd_open # # x32-specific system call numbers start at 512 to avoid cache impact diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index 5fa0ee1c8e00..782b81945ccc 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -404,3 +404,4 @@ 431 common fsconfig sys_fsconfig 432 common fsmount sys_fsmount 433 common fspick sys_fspick +434 common pidfd_open sys_pidfd_open diff --git a/include/linux/pid.h b/include/linux/pid.h index 3c8ef5a199ca..c938a92eab99 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -67,6 +67,7 @@ struct pid extern struct pid init_struct_pid; extern const struct file_operations pidfd_fops; +extern int pidfd_create(struct pid *pid); static inline struct pid *get_pid(struct pid *pid) { diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index e2870fe1be5b..989055e0b501 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -929,6 +929,7 @@ asmlinkage long sys_clock_adjtime32(clockid_t which_clock, struct old_timex32 __user *tx); asmlinkage long sys_syncfs(int fd); asmlinkage long sys_setns(int fd, int nstype); +asmlinkage long sys_pidfd_open(pid_t pid, unsigned int flags); asmlinkage long sys_sendmmsg(int fd, struct mmsghdr __user *msg, unsigned int vlen, unsigned flags); asmlinkage long sys_process_vm_readv(pid_t pid, diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index a87904daf103..e5684a4512c0 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -844,9 +844,11 @@ __SYSCALL(__NR_fsconfig, sys_fsconfig) __SYSCALL(__NR_fsmount, sys_fsmount) #define __NR_fspick 433 __SYSCALL(__NR_fspick, sys_fspick) +#define __NR_pidfd_open 434 +__SYSCALL(__NR_pidfd_open, sys_pidfd_open) #undef __NR_syscalls -#define __NR_syscalls 434 +#define __NR_syscalls 435 /* * 32 bit systems traditionally used different diff --git a/kernel/fork.c b/kernel/fork.c index b4cba953040a..c3df226f47a1 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1724,7 +1724,7 @@ const struct file_operations pidfd_fops = { * Return: On success, a cloexec pidfd is returned. * On error, a negative errno number will be returned. */ -static int pidfd_create(struct pid *pid) +int pidfd_create(struct pid *pid) { int fd; diff --git a/kernel/pid.c b/kernel/pid.c index 89548d35eefb..8fc9d94f6ac1 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -37,6 +37,7 @@ #include <linux/syscalls.h> #include <linux/proc_ns.h> #include <linux/proc_fs.h> +#include <linux/sched/signal.h> #include <linux/sched/task.h> #include <linux/idr.h> @@ -450,6 +451,48 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns) return idr_get_next(&ns->idr, &nr); } +/** + * pidfd_open() - Open new pid file descriptor. + * + * @pid: pid for which to retrieve a pidfd + * @flags: flags to pass + * + * This creates a new pid file descriptor with the O_CLOEXEC flag set for + * the process identified by @pid. Currently, the process identified by + * @pid must be a thread-group leader. This restriction currently exists + * for all aspects of pidfds including pidfd creation (CLONE_PIDFD cannot + * be used with CLONE_THREAD) and pidfd polling (only supports thread group + * leaders). + * + * Return: On success, a cloexec pidfd is returned. + * On error, a negative errno number will be returned. + */ +SYSCALL_DEFINE2(pidfd_open, pid_t, pid, unsigned int, flags) +{ + int fd, ret; + struct pid *p; + + if (flags) + return -EINVAL; + + if (pid <= 0) + return -EINVAL; + + p = find_get_pid(pid); + if (!p) + return -ESRCH; + + ret = 0; + rcu_read_lock(); + if (!pid_task(p, PIDTYPE_TGID)) + ret = -EINVAL; + rcu_read_unlock(); + + fd = ret ?: pidfd_create(p); + put_pid(p); + return fd; +} + void __init pid_idr_init(void) { /* Verify no one has done anything silly: */ -- 2.21.0

5 years

2
4
0 0

[PATCH v4 00/18] kunit: introduce KUnit, the Linux kernel unit testing framework

by Brendan Higgins

## TLDR A quick follow up to yesterday's revision. I got some feedback that I wanted to incorporate before anyone else read the update. For this reason, I will leave a TLDR of the biggest changes since v2. Biggest things to look out for (since v2): - KUnit core now outputs results in TAP14. - Heavily reworked tools/testing/kunit/kunit.py - Changed how parsing works. - Added testing. - Greg, Logan, you might want to re-review this. - Added documentation on how to use KUnit on non-UML kernels. You can see the docs rendered here[1]. There is still some discussion going on on the [PATCH v2 00/17] thread, but I wanted to get some of these updates out before they got too stale (and too difficult for me to keep track of). I hope no one minds. ## Background This patch set proposes KUnit, a lightweight unit testing and mocking framework for the Linux kernel. Unlike Autotest and kselftest, KUnit is a true unit testing framework; it does not require installing the kernel on a test machine or in a VM (however, KUnit still allows you to run tests on test machines or in VMs if you want) and does not require tests to be written in userspace running on a host kernel. Additionally, KUnit is fast: From invocation to completion KUnit can run several dozen tests in under a second. Currently, the entire KUnit test suite for KUnit runs in under a second from the initial invocation (build time excluded). KUnit is heavily inspired by JUnit, Python's unittest.mock, and Googletest/Googlemock for C++. KUnit provides facilities for defining unit test cases, grouping related test cases into test suites, providing common infrastructure for running tests, mocking, spying, and much more. ## What's so special about unit testing? A unit test is supposed to test a single unit of code in isolation, hence the name. There should be no dependencies outside the control of the test; this means no external dependencies, which makes tests orders of magnitudes faster. Likewise, since there are no external dependencies, there are no hoops to jump through to run the tests. Additionally, this makes unit tests deterministic: a failing unit test always indicates a problem. Finally, because unit tests necessarily have finer granularity, they are able to test all code paths easily solving the classic problem of difficulty in exercising error handling code. ## Is KUnit trying to replace other testing frameworks for the kernel? No. Most existing tests for the Linux kernel are end-to-end tests, which have their place. A well tested system has lots of unit tests, a reasonable number of integration tests, and some end-to-end tests. KUnit is just trying to address the unit test space which is currently not being addressed. ## More information on KUnit There is a bunch of documentation near the end of this patch set that describes how to use KUnit and best practices for writing unit tests. For convenience I am hosting the compiled docs here[2]. Additionally for convenience, I have applied these patches to a branch[3]. The repo may be cloned with: git clone https://kunit.googlesource.com/linux This patchset is on the kunit/rfc/v5.1/v4 branch. ## Changes Since Last Version As I mentioned above, there are a significant number of updates since v2: - Converted KUnit core to print test results in TAP14 format as suggested by Greg and Frank. - Heavily reworked tools/testing/kunit/kunit.py - Changed how parsing works. - Added testing. - Added documentation on how to use KUnit on non-UML kernels. You can see the docs rendered here[1]. - Added a new set of EXPECTs and ASSERTs for pointer comparison. - Removed more function indirection as suggested by Logan. - Added a new patch that adds `kunit_try_catch_throw` to objtool's noreturn list. - Fixed a number of minorish issues pointed out by Shuah, Masahiro, and kbuild bot. Nevertheless, there are only a couple of minor updates since v3: - Added more context to the changelog on the objtool patch, as per Peter's request. - Moved all KUnit documentation under the Documentation/dev-tools/ directory as per Jonathan's suggestion. [1] https://google.github.io/kunit-docs/third_party/kernel/docs/usage.html#kuni… [2] https://google.github.io/kunit-docs/third_party/kernel/docs/ [3] https://kunit.googlesource.com/linux/+/kunit/rfc/v5.1/v4 -- 2.21.0.1020.gf2820cf01a-goog

5 years, 1 month

3
35
0 0

[PATCH net-next v2 0/3] UDP GSO audit tests

by Fred Klassen

Updates to UDP GSO selftests ot optionally stress test CMSG subsytem, and report the reliability and performance of both TX Timestamping and ZEROCOPY messages. Fred Klassen (3): net/udpgso_bench_tx: options to exercise TX CMSG net/udpgso_bench.sh add UDP GSO audit tests net/udpgso_bench.sh test fails on error tools/testing/selftests/net/udpgso_bench.sh | 51 +++- tools/testing/selftests/net/udpgso_bench_tx.c | 324 ++++++++++++++++++++++++-- 2 files changed, 357 insertions(+), 18 deletions(-) -- 2.11.0

5 years, 1 month

2
8
0 0

[PATCH v5 00/10] Support using MSI interrupts in ntb_transport

by Logan Gunthorpe

This is another resend as there has been no feedback since v4. Seems Jon has been MIA this past cycle so hopefully he appears on the list soon. I've addressed the feedback so far and rebased on the latest kernel and would like this to be considered for merging this cycle. The only outstanding issue I know of is that it still will not work with IDT hardware, but ntb_transport doesn't work with IDT hardware and there is still no sensible common infrastructure to support ntb_peer_mw_set_trans(). Thus, I decline to consider that complication in this patchset. However, I'll be happy to review work that adds this feature in the future. Also, as the port number and resource index stuff is a bit complicated, I made a quick out of tree test fixture to ensure it's correct[1]. As an excerise I also wrote some test code[2] using the upcomming KUnit feature. Logan [1] https://repl.it/repls/ExcitingPresentFile [2] https://github.com/sbates130272/linux-p2pmem/commits/ntb_kunit -- Changes in v5: * Rebased onto v5.2-rc1 (plus the patches in ntb-next) -- Changes in v4: * Rebased onto v5.1-rc6 (No changes) * Numerous grammar and spelling mistakes spotted by Bjorn -- Changes in v3: * Rebased onto v5.1-rc1 (Dropped the first two patches as they have been merged, and cleaned up some minor conflicts in the PCI tree) * Added a new patch (#3) to calculate logical port numbers that are port numbers from 0 to (number of ports - 1). This is then used in ntb_peer_resource_idx() to fix the issues brought up by Serge. * Fixed missing __iomem and iowrite calls (as noticed by Serge) * Added patch 10 which describes ntb_msi_test in the documentation file (as requested by Serge) * A couple other minor nits and documentation fixes -- Changes in v2: * Cleaned up the changes in intel_irq_remapping.c to make them less confusing and add a comment. (Per discussion with Jacob and Joerg) * Fixed a nit from Bjorn and collected his Ack * Added a Kconfig dependancy on CONFIG_PCI_MSI for CONFIG_NTB_MSI as the Kbuild robot hit a random config that didn't build without it. * Worked in a callback for when the MSI descriptor changes so that the clients can resend the new address and data values to the peer. On my test system this was never necessary, but there may be other platforms where this can occur. I tested this by hacking in a path to rewrite the MSI descriptor when I change the cpu affinity of an IRQ. There's a bit of uncertainty over the latency of the change, but without hardware this can acctually occur on we can't test this. This was the result of a discussion with Dave. -- This patch series adds optional support for using MSI interrupts instead of NTB doorbells in ntb_transport. This is desirable seeing doorbells on current hardware are quite slow and therefore switching to MSI interrupts provides a significant performance gain. On switchtec hardware, a simple apples-to-apples comparison shows ntb_netdev/iperf numbers going from 3.88Gb/s to 14.1Gb/s when switching to MSI interrupts. To do this, a couple changes are required outside of the NTB tree: 1) The IOMMU must know to accept MSI requests from aliased bused numbers seeing NTB hardware typically sends proxied request IDs through additional requester IDs. The first patch in this series adds support for the Intel IOMMU. A quirk to add these aliases for switchtec hardware was already accepted. See commit ad281ecf1c7d ("PCI: Add DMA alias quirk for Microsemi Switchtec NTB") for a description of NTB proxy IDs and why this is necessary. 2) NTB transport (and other clients) may often need more MSI interrupts than the NTB hardware actually advertises support for. However, seeing these interrupts will not be triggered by the hardware but through an NTB memory window, the hardware does not actually need support or need to know about them. Therefore we add the concept of Virtual MSI interrupts which are allocated just like any other MSI interrupt but are not programmed into the hardware's MSI table. This is done in Patch 2 and then made use of in Patch 3. The remaining patches in this series add a library for dealing with MSI interrupts, a test client and finally support in ntb_transport. The series is based off of v5.1-rc6 plus the patches in ntb-next. A git repo is available here: https://github.com/sbates130272/linux-p2pmem/ ntb_transport_msi_v4 Thanks, Logan -- Logan Gunthorpe (10): PCI/MSI: Support allocating virtual MSI interrupts PCI/switchtec: Add module parameter to request more interrupts NTB: Introduce helper functions to calculate logical port number NTB: Introduce functions to calculate multi-port resource index NTB: Rename ntb.c to support multiple source files in the module NTB: Introduce MSI library NTB: Introduce NTB MSI Test Client NTB: Add ntb_msi_test support to ntb_test NTB: Add MSI interrupt support to ntb_transport NTB: Describe the ntb_msi_test client in the documentation. Documentation/ntb.txt | 27 ++ drivers/ntb/Kconfig | 11 + drivers/ntb/Makefile | 3 + drivers/ntb/{ntb.c => core.c} | 0 drivers/ntb/msi.c | 415 +++++++++++++++++++++++ drivers/ntb/ntb_transport.c | 169 ++++++++- drivers/ntb/test/Kconfig | 9 + drivers/ntb/test/Makefile | 1 + drivers/ntb/test/ntb_msi_test.c | 433 ++++++++++++++++++++++++ drivers/pci/msi.c | 54 ++- drivers/pci/switch/switchtec.c | 12 +- include/linux/msi.h | 8 + include/linux/ntb.h | 196 ++++++++++- include/linux/pci.h | 9 + tools/testing/selftests/ntb/ntb_test.sh | 54 ++- 15 files changed, 1386 insertions(+), 15 deletions(-) rename drivers/ntb/{ntb.c => core.c} (100%) create mode 100644 drivers/ntb/msi.c create mode 100644 drivers/ntb/test/ntb_msi_test.c -- 2.20.1

5 years, 1 month

2
12
0 0

[PATCH v4 0/3] Fix vDSO clock_getres()

by Vincenzo Frascino

clock_getres in the vDSO library has to preserve the same behaviour of posix_get_hrtimer_res(). In particular, posix_get_hrtimer_res() does: sec = 0; ns = hrtimer_resolution; and hrtimer_resolution depends on the enablement of the high resolution timers that can happen either at compile or at run time. A possible fix is to change the vdso implementation of clock_getres, keeping a copy of hrtimer_resolution in vdso data and using that directly [1]. This patchset implements the proposed fix for arm64, powerpc, s390, nds32 and adds a test to verify that the syscall and the vdso library implementation of clock_getres return the same values. Even if these patches are unified by the same topic, there is no dependency between them, hence they can be merged singularly by each arch maintainer. Note: arm64 and nds32 respective fixes have been merged in 5.2-rc1, hence they have been removed from this series. [1] https://marc.info/?l=linux-arm-kernel&m=155110381930196&w=2 Changes: -------- v4: - Address review comments. v3: - Rebased on 5.2-rc1. - Address review comments. v2: - Rebased on 5.1-rc5. - Addressed review comments. Cc: Christophe Leroy <christophe.leroy(a)c-s.fr> Cc: Benjamin Herrenschmidt <benh(a)kernel.crashing.org> Cc: Paul Mackerras <paulus(a)samba.org> Cc: Michael Ellerman <mpe(a)ellerman.id.au> Cc: Martin Schwidefsky <schwidefsky(a)de.ibm.com> Cc: Heiko Carstens <heiko.carstens(a)de.ibm.com> Cc: Shuah Khan <shuah(a)kernel.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: Arnd Bergmann <arnd(a)arndb.de> Signed-off-by: Vincenzo Frascino <vincenzo.frascino(a)arm.com> Vincenzo Frascino (3): powerpc: Fix vDSO clock_getres() s390: Fix vDSO clock_getres() kselftest: Extend vDSO selftest to clock_getres arch/powerpc/include/asm/vdso_datapage.h | 2 + arch/powerpc/kernel/asm-offsets.c | 2 +- arch/powerpc/kernel/time.c | 1 + arch/powerpc/kernel/vdso32/gettimeofday.S | 7 +- arch/powerpc/kernel/vdso64/gettimeofday.S | 7 +- arch/s390/include/asm/vdso.h | 1 + arch/s390/kernel/asm-offsets.c | 2 +- arch/s390/kernel/time.c | 1 + arch/s390/kernel/vdso32/clock_getres.S | 12 +- arch/s390/kernel/vdso64/clock_getres.S | 10 +- tools/testing/selftests/vDSO/Makefile | 2 + .../selftests/vDSO/vdso_clock_getres.c | 124 ++++++++++++++++++ 12 files changed, 155 insertions(+), 16 deletions(-) create mode 100644 tools/testing/selftests/vDSO/vdso_clock_getres.c -- 2.21.0

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[PATCH for 5.2 08/12] rseq/selftests: arm: use udf instruction for RSEQ_SIG

by Mathieu Desnoyers

Use udf as the guard instruction for the restartable sequence abort handler. Previously, the chosen signature was not a valid instruction, based on the assumption that it could always sit in a literal pool. However, there are compilation environments in which literal pools are not availble, for instance execute-only code. Therefore, we need to choose a signature value that is also a valid instruction. Handle compiling with -mbig-endian on ARMv6+, which generates binaries with mixed code vs data endianness (little endian code, big endian data). Else mismatch between code endianness for the generated signatures and data endianness for the RSEQ_SIG parameter passed to the rseq registration will trigger application segmentation faults when the kernel try to abort rseq critical sections. Prior to ARMv6, -mbig-endian generates big-endian code and data, so endianness should not be reversed in that case. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> CC: Peter Zijlstra <peterz(a)infradead.org> CC: Thomas Gleixner <tglx(a)linutronix.de> CC: Joel Fernandes <joelaf(a)google.com> CC: Catalin Marinas <catalin.marinas(a)arm.com> CC: Dave Watson <davejwatson(a)fb.com> CC: Will Deacon <will.deacon(a)arm.com> CC: Shuah Khan <shuah(a)kernel.org> CC: Andi Kleen <andi(a)firstfloor.org> CC: linux-kselftest(a)vger.kernel.org CC: "H . Peter Anvin" <hpa(a)zytor.com> CC: Chris Lameter <cl(a)linux.com> CC: Russell King <linux(a)arm.linux.org.uk> CC: Michael Kerrisk <mtk.manpages(a)gmail.com> CC: "Paul E . McKenney" <paulmck(a)linux.vnet.ibm.com> CC: Paul Turner <pjt(a)google.com> CC: Boqun Feng <boqun.feng(a)gmail.com> CC: Josh Triplett <josh(a)joshtriplett.org> CC: Steven Rostedt <rostedt(a)goodmis.org> CC: Ben Maurer <bmaurer(a)fb.com> CC: linux-api(a)vger.kernel.org CC: Andy Lutomirski <luto(a)amacapital.net> CC: Andrew Morton <akpm(a)linux-foundation.org> CC: Linus Torvalds <torvalds(a)linux-foundation.org> --- tools/testing/selftests/rseq/rseq-arm.h | 52 +++++++++++++++++++++++++++++++-- 1 file changed, 50 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h index 5f262c54364f..e8ccfc37d685 100644 --- a/tools/testing/selftests/rseq/rseq-arm.h +++ b/tools/testing/selftests/rseq/rseq-arm.h @@ -5,7 +5,54 @@ * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com> */ -#define RSEQ_SIG 0x53053053 +/* + * RSEQ_SIG uses the udf A32 instruction with an uncommon immediate operand + * value 0x5de3. This traps if user-space reaches this instruction by mistake, + * and the uncommon operand ensures the kernel does not move the instruction + * pointer to attacker-controlled code on rseq abort. + * + * The instruction pattern in the A32 instruction set is: + * + * e7f5def3 udf #24035 ; 0x5de3 + * + * This translates to the following instruction pattern in the T16 instruction + * set: + * + * little endian: + * def3 udf #243 ; 0xf3 + * e7f5 b.n <7f5> + * + * pre-ARMv6 big endian code: + * e7f5 b.n <7f5> + * def3 udf #243 ; 0xf3 + * + * ARMv6+ -mbig-endian generates mixed endianness code vs data: little-endian + * code and big-endian data. Ensure the RSEQ_SIG data signature matches code + * endianness. Prior to ARMv6, -mbig-endian generates big-endian code and data + * (which match), so there is no need to reverse the endianness of the data + * representation of the signature. However, the choice between BE32 and BE8 + * is done by the linker, so we cannot know whether code and data endianness + * will be mixed before the linker is invoked. + */ + +#define RSEQ_SIG_CODE 0xe7f5def3 + +#ifndef __ASSEMBLER__ + +#define RSEQ_SIG_DATA \ + ({ \ + int sig; \ + asm volatile ( "b 2f\n\t" \ + "1: .inst " __rseq_str(RSEQ_SIG_CODE) "\n\t" \ + "2:\n\t" \ + "ldr %[sig], 1b\n\t" \ + : [sig] "=r" (sig)); \ + sig; \ + }) + +#define RSEQ_SIG RSEQ_SIG_DATA + +#endif #define rseq_smp_mb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") #define rseq_smp_rmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") @@ -78,7 +125,8 @@ do { \ __rseq_str(table_label) ":\n\t" \ ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ - ".word " __rseq_str(RSEQ_SIG) "\n\t" \ + ".arm\n\t" \ + ".inst " __rseq_str(RSEQ_SIG_CODE) "\n\t" \ __rseq_str(label) ":\n\t" \ teardown \ "b %l[" __rseq_str(abort_label) "]\n\t" -- 2.11.0

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Linux-kselftest-mirror May 2019